一个有效的水力动力学描述行进的虫
Dan Gorbonos1, Felix B Oberhauser2,3, Luke L Costello1
1Department of Collective Behaviour, Max Planck Institute of Animal Behavior, 78464 Konstanz, Germany.
Physical biology
|January 24, 2024
概括
复杂的系统可以使用流体动力学来描述. 虫游行乐队表现出集体运动,验证了宏观的水力动力学模型,以了解群的行为及其大规模属性.
科学领域:
- 复杂的系统复杂的系统.
- 集体行为 集体行为
- 生物物理学的生物物理.
背景情况:
- 了解微观相互作用和宏观性质之间的关系是复杂系统的一个关键挑战.
- 对生物系统的宏观模型的存在和描述能力仍然不清楚.
研究的目的:
- 为了调查一个复杂的生物系统的宏观描述的有效性.
- 用沙漠虫 (Schistocerca gregaria) 的集体运动作为流体动力学的模型.
主要方法:
- 在肯尼亚疫情爆发期间,拍摄虫在游行乐队中,并自动跟踪个人.
- 分析虫的空间分布和最近邻居拓.
- 重建个别轨迹以与诸如Toner-Tu方程等理论模型进行比较.
主要成果:
- 虫表现出同源分布,但在高密度区域显示出局部排序,类似于有序流体.
- 各个虫的轨迹是对齐的,与一维的Toner-Tu方程一致.
- 有效的虫"压力"与高度极化段的密度线性增加.
结论:
- 一个有效的水力动力学描述,特别是Toner-Tu方程,可以捕捉沙漠虫游行乐队的流动动力学.
- 这项研究证明了宏观物理模型对复杂的生物系统 (如昆虫群) 的适用性.
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